Knife structure



Jan. 27, 1970- J, R. URSCHEL KNIFE STRUCTURE Filed April 12. 1967INVENTOR. Jo: P. URSCHEL My ATTORNEY United States Patent 3,491,817KNIFE STRUCTURE Joe R. Urschel, 202 Michigan Ave., Valparaiso, Ind.46383 Filed Apr. 12, 1967, Ser. No. 630,347 Int. Cl. A01d 23/04; A221)/08 US. Cl. 146-86 12 Claims ABSTRACT OF THE DISCLOSURE The invention isprimarily directed to hearing means for maintaining the cutting edge ofa knife in a predetermined relationship to a rotatable cylinder.

The subject invention relates generally to a knife assembly and moreparticularly is directed to an assembly for cutting or snipping off theends of a product, such as string beans, which are adapted to protrudeoutwardly through peripheral openings provided in a cylinder or drumwhen the latter is rotated.

Machines or equipment for effecting such cutting are exemplified, forexample, in my Patent Nos. 2,705,516, dated Apr. 5, 1955; 3,304,974,dated Feb. 21, 1967; 3,304,975, dated Feb. 21, 1967; and in my pendingap plication Ser. No. 461,713, now Patent No. 3,318,350.

The invention, among other things is directed to a knife assembly whichincludes unique improvements in design and construction over thoseembodied in the patents and application above referred to.

A significant object of the invention is to provide an organization inwhich the life of the knives of the knife assembly and a cylinder areappreciably prolonged, as compared to those illustrated in the abovepatents and application.

More specifically, an object of the invention is to provide an assemblycomprising a support for knives, resiliently flexible means for urgingthe knives toward a rotatable cylinder for cutting the ends off stringbeans, and means carried by the assembly for hearing engagement with thecylinder for maintaining the knives in a predetermined position relativeto the cylinder.

A particular object of the invention is to provide a bearing means whichalso serves to stabilize the knife assembly and particularly the knivesthereof and reduce chatter, vibration, and noise.

A specific but important object of the invention is to provide a bearingmeans which will substantially prevent a galling or scoring of theperipheral surface of the cylinder and provide a relatively largebearing area for engagement with such surface, as compared to thecutting areas or edge of the knife which may or may not engage suchperipheral surface.

The invention also offers advantages with respect to providing bearingmeans which is preferably of a nonmetallic character, one which isresiliently flexible, efficient, more or less self-lubricating, andexceptionally durable for the purpose intended.

Additional objects and advantages of the invention will become apparentafter the description hereinafter set forth is considered in conjunctionwith the drawings annexed hereto.

In the drawings:

FIGURE 1 is a front elevational view of a knife assembly, embodying theinvention, carried by a support and operatively associated with acylinder, with only a portion of the support and cylinder being shown;

FIGURE 2 is a side elevational view of a portion of the structure shownin FIGURE 1;

FIGURE 3 is an enlarged transverse section taken substantially on theline 33 of FIGURE 1, showing a unit or assembly comprising a knife and abearing means preferably secured thereto by cement;

FIGURE 4 is a bottom view of the knife and bearing means shown in FIGURE3;

FIGURE 5 is an edge elevational view of the structure shown in FIGURE 4;

FIGURE 6 is a bottom view of a modified unit comprising a knife andbearing means, in which fastening means, preferably in the form ofrivets, is utilized to connect the components;

FIGURE 7 is a transverse section taken substantially on line 7-7 ofFIGURE 6;

FIGURE 8 is a view similar to FIGURE 6 showing a backing or reinforcingmember secured against a bearing means; and

FIGURE 9 is a transverse section taken substantially on line 99 ofFIGURE 8.

Referring to FIGURE 1 of the drawing, there is disclosed a portion ofrotatable cylinder 1 and a knife assembly 2 which is operativelyassociated with the cylinder. In practice, as exemplified in the patentand applications above referred to, a plurality of substantiallycorresponding knife assemblies is utilized, but only one assembly isdepicted in the drawings of the subject application.

The cylinder is provided with rows of circumferentially spaced openingsor slots 3 through which the ends of a product, such as string beans,may be caused to protrude outwardly when the cylinder is rotated.

The knife assembly, as exemplified herein, comprises a structuregenerally designated 4 supporting a plurality of three curved knives 5,attaching means generally designated 6 for detachably connecting theassembly to a horizontal mounting or cylindrical support 7 disposedalongside the cylinder and resiliently flexible means, preferably in theform of a single leaf spring 8 which is detachably connected to theknife supporting structure 4 and the attaching means '6. Obviously, aplurality of leaf springs may be utilized in lieu of the spring 8.

The knife supporting structure 4, which will now be described, may bedesigned and constructed in various ways but, as illustrated, it is inthe form of an articulated frame, preferably cast, and comprises anelongate rigid bar 9 and a plurality of three substantiallycorresponding equally spaced elongate members 10 and a pair of aperturedoffsets 11 provided with planar seat means 12 (one shown) for anenlarged apertured extremity 13 of the spring 8. A pair of fasteningmeans, such as bolts 14, extend through the apertures in the offsets 11and the extremity 13 for firmly detachably connected the spring to theframe. It will be observed that the members 10 are offset from the baras indicated at 10 and disposed in a parallel relationship at obliqueangles with respect to the longitudinal axis of the bar 9 and that eachincludes an upper relatively long extremity and a shorter lowerextremity.

It will be noted that the rear side of each of the members is providedwith a concave seat 15 (one shown) which extends throughout the fulllength of the member at an inclination with respect to its longitudinalaxis. The upper extremity of each of the members is preferablyreinforced by a longitudinally extending generally triangular rib 16which merges into the bar 9 in order to impart strength to the membersas well as to the connections between the members and bar. The ends ofthe members 10 are provided with apertures 17 (one shown) and fasteningmeans preferably in the form of bolts 18 which extend through theapertures 17 and through apertures 19 provided in the extremities of theknives 5, as best depicted in FIGURES 2, 3 and 4. Each of the knives 5is preferably resiliently flexible, of uniform thickness,

generally rectangular and of a width and length somewhat greater thanthe width and length of each of the members 10, as shown in FIGURE 1.Each knife is also preferably bevelled at its ends as indicated at 20and includes an elongate sharpened edge 50 for severing the ends off thebeans and a lower end which is bent or angled outwardly, as indicated at22 whereby to prevent the knives from gouging into the cylinder. Eachknife is also preferably bevelled at 51 throughout its length adjacentto the edge 50.

The resiliently flexible means 8 is preferably in the form of a singleor individual flat or planar spring of uniform thickness. This spring issubstantially uniformly resiliently flexible throughout the majorportion of its length and is relatively wide in order to impartstability thereto as well as the knife supporting structure in itsrelation to the cylinder. The upper extremity of the spring is enlargedat 13, as stated above, and its lower extremity is similarly enlarged asat 23 and provided with apertures for receiving fasteners 35, as will bedescribed more in detail subsequently. It will be observed that theupper extremity 13 of the spring is preferably slightly offset asindicated at 24 whereby to assist in maintaining the knives in a correctattitude for operative relationship with respect to the cylinder.

The attaching means generally designated 6 may be designed andconstructed in various ways but, as illustrated herein, it preferablycomprises a substantially semicylindrical rigid block 25 having an innersubstantially semicylindrical surface of appreciable area for receivingand engaging an under side of the cylindrical surface of the support 7.A substantially U-shaped element 27 has a curved portion which engagesan upper side of the support and legs 29 which straddle the support andcarry nuts 30 for adjustably clamping the support between the block andelement. The nuts of the bolts 30 may be readily loosened and tightenedto enable an operator to correctly adjust and firmly secure theattaching means on the support 7 so that the spring will applysufficient pressure to correctly urge all of the edges of the knivestoward the periphery of the cylinder for efficiently Cutting off theends of the beans. The spring, due to its uniform thickness,substantially uniform relatively wide width throughout the major portionof its length and enlarged extremities is rendered relatively stable andefficient for substantially everlasting use in maintaining the knifesupporting structure in a correct stabilized operative relationship withrespect to the cylinder and at the same time afford a setup whereby thestructure may be automatically retracted and re-urged toward thecylinder.

As pointed out above the principal object of the subject invention is toprovide a knife assembly with bearing means whereby to maintain one ormore knives of the assembly in a predetermined operative relationshipwith respect to the peripheral surface of the cylinder. More explicitly,the invention involves locating or interposing bearing means between theknife supporting structure and the cylinder for the purpose ofpreventing or minimizing metal-to-metal contact between the knives andthe cylinder.

The bearing means for accomplishing the above objective may be designedand constructed in various ways. For example, all of the bearing meansexemplified in FIGURES 2 through 9, are preferably elongated,substantially rectangular in cross-section, and, as shown in FIGURES 2through 5, constructed from a non-metallic material commonly referred toin the industry as urethane. This material or product has proven to beresilient, more or less self-lubricating, non-galling, exceptionallydurable from the standpoint of wear, and readily returnable to itsoriginal shape or size after distortion or compression.

As exemplified in FIGURES 2 through 5, for example, a bearing means 60is provided with a bevel or chamfer 61. This bearing means is preferablybonded or otherwise permanently secured against an underside or surfaceof the knife 5 by cement 62 or some other suitable bonding agent, asshown in FIGURE 3. The bearing means is preferably of a lengthsubstantially corresponding to the length of the knife and the beveledsurface 61 is preferably disposed in a plane substantially parallel tothe bevel 51 of the knife, as shown in FIGURE 3, so that the bevel ofthe knife is spaced in a plane substantially parallel to the peripheralsurface of the cylinder, the space or gap therebetween being within arange of .005" and .025.

With the above organization, the cutting edge 51 of each of the knivesis normally maintained in spaced relationship with respect to thecylinder in order to prevent metal-to-metal contact therebetween andthereby prevent galling and/ or scoring of the cylinder. Moreover, thebearing means serve to provide relatively large bearing surfaces orareas which engage the cylinder for the purpose of stabilizing theposition of the knives individually as well as jointly. Furthermore, theorganization assists in preventing dulling and/ or accidentally nickingor damaging of the knife edges.

Referring to FIGURES 6 and 7, there is exemplified a modified structureor unit having a different mode of securing a bearing means 70 to eachof the knives. More specifically in this respect, each of the bearingmeans 70 substantially corresponds to the bearing means 60, except thatit is secured to a knife by means of a plurality of fastening meanspreferably in the form of rivets 71 which extend through alignedapertures provide therefor in the knife and bearing means as clearlyshown.

Referring to the .modified structure or unit illustrated in FIGURES 8and 9 of the drawing there is shown a bearing means which substantiallycorresponds to the bearing means 60 and 70 above referred to. Thebearing means 80 is preferably secured to a knife by a plurality ofrivets 81 which extend through aligned apertures provided therefor inthe knife and bearing means and also through apertures provided in abacking or reinforcing member 83. The backing members respectively serveto more firmly secure or anchor the bearing means in relation to theknives.

Attention is directed to the fact that although an objective of theinvention is to primarily maintain the cutting edges of the knives inspaced relation to the cylinder, it is to be appreciated that thebearing means after long and hard usage may become worn to an extentwhereby the bevels of the knives will become aligned with the wearingsurfaces of the bearing means and bear against the cylinder. Morespecifically, the worn surface of the bearing means 80 is illustrated bya dotted line 84 in FIGURE 9. Otherwise expressed, the bearing means,irrespective of whether they do or do not space the cutting edges of theknives in relation to the cylinder do in fact provide substantialbearing surfaces or areas which serve to prevent and/or minimize wearbetween the knives and cylinder and efiiciently stabilize the knifesupporting structure and knives and particularly the cutting edges ofthe latter. The bearing means also serves to reduce friction between theknife assembly and cylinder.

In addition to the above, and insofar as known, all commercial beansnipping machines that have been built by anyone have had knives incontact with a rotating cylinder. The knives have been made of eithercarbon knife steel or stainless knife steel and the cylinders have beenmade of either ordinary steel, stainless steel, bronze or plastic. Themost serious problem with such machines has been that the knives wearthe cylinder until it becomes useless within a relatively short time. Nosuitable material acting as a lubricant can be used because any suchmaterial will contaminate the food product. Water is the only knownliquid that can be used on this equipment at the time green beans arebeing processed. In this application, water proves itself to be a poorlubricant.

Although bean snippet cylinders are being made of plastic, no plastichas yet been found with sufiicient rigidity and strength and yet remaina good wearing material with sharp knives running against it.Unfortunately, when selecting the best materials for both the cylinderand the knives, the two materials are not compatible for rubbing againsteach other.

Having thus described my invention, it is obvious that various othermodifications may be made in the same manner without departing from thespirit of the invention and, therefore, I do not wish to be understoodas limiting myself to the exact forms, constructions, arrangements, andcombinations of parts herein shown and described.

I claim:

1. In combination: a cylinder having a cylindrical wall provided with aplurality of openings whereby ends of elongated items adapted formovement in the cylinder may extend therethrough, a support, anelongated knife secured to said support and provided with an elongatedcutting edge for snipping off such ends, means for urging the supportand knife toward said wall, and elongated bearing means secured inrelation to an under surface of said knife and extending lengthwisethereof engaging said wall for locating said cutting edge in apredetermined position with respect thereto.

2. In combination: a cylinder adapted for rotation and having acylindrical wall provided with a plurality of openings through whichends of a multitude of items adapted for movement in the cylinder mayproject, an assembly comprising a support and a knife carried by saidsupport having a cutting edge for cutting off such ends, means forurging the assembly toward said Wall, and means carried by said assemblyproviding a substantial bearing surface engaging said wall formaintaining said cutting edge in a predetermined position with respectthereto.

3. In combination: a cylinder adapted for rotation and having acylindrical wall provided with a plurality of openings whereby elongatedproducts disposed in the cylinder and having ends may protrude throughsaid openings, a support carrying a knife having a cutting edge forcutting off such ends, means for urging said support and said knife as aunit toward said cylinder, and means carried by said knife and bearingagainst said cylinder for stabilizing said knife and maintaining itscuttng edge in a predetermined relationship to said wall.

4. The combination defined in claim 3, in which said bearing meansserves to space said cutting edge a predetermined distance away fromsaid wall.

5. The combination defined in claim 3, in which said bearing means issecured to said knife by cement.

6. The combination defined in claim 3, in which said bearing means issecured to said knife by fasteners extending through said knife andbearing means.

7. The combination defined in claim 3, including a reinforcement withsaid bearing means being secured between said knife and reinforcement.

8. The combination defined in claim 2, in which said bearing means isconstructed from urethane.

9. Knife structure for use with a rotatable cylinder which has acylindrical wall provided with a plurality of openings whereby ends ofelongated items adapted for movement in the cylinder may extend throughthe openings, said knife structure comprising a support and an elongatedknife secured to said support and provided with an elongated cuttingedge for snipping 01f such ends, means for mounting the support forurging the support and knife toward the wall of such a cylinder, andelongated bearing means secured in relation to an under surface of saidknife and extending lengthwise thereof for engaging such a wall forlocating said cutting edge in a predetermined position with respectthereto.

10. An assembly for use with a rotatable cylinder having a cylindricalwall provided with a plurality of openings through which ends of amultitude of items adapted for movement in the cylinder may project,said assembly comprising a support and a knife carried by said supporthaving a cutting edge for cutting off such ends, means whereby theassembly may be urged toward such a wall, and means carried by saidassembly providing a substantial bearing surface for engaging such awall for maintaining said cutting edge in a predetermined position withrespect thereto.

11. Knife structure comprising: a support carrying a knife having acutting edge for cutting 01f ends of items which are adapted to tumbleand project through openings in a cylindrical wall of a rotatablecylinder, means whereby said support and knife as a unit may be urgedtoward such a cylinder, and means carried by said knife for bearingagainst such a wall for stabilizing said knife and maintaining itscutting edge in a predetermined relationship to such a wall.

12. The structure defined in claim 11, in which said bearing means isconstructed from urethane.

References Cited UNITED STATES PATENTS 2,769,236 11/1936 Phillips et a1.30-l69 3,087,243 4/1963 Matousek 30-169 3,145,607 8/1964 Geary 83701 X3,304,975 2/1967 Wrschel 146-86 W. GRAYDON ABERCROMBIE, Primary Examiner

